Luteolin sensitizes the antitumor effect of cisplatin in drug-resistant ovarian cancer via induction of apoptosis and inhibition of cell migration and invasion

Luteolin, a polyphenolic flavone, has been demonstrated to exert anti-tumor activity in various cancer types. Cisplatin drug resistance is a major obstacle in the management of ovarian cancer. In the present study, we investigated the chemo-sensitizing effect of luteolin in both cisplatin-resistant ovarian cancer cell line and a mice xenotransplant model. In vitro, CCK-8 assay showed that luteolin inhibited cell proliferation in a dose-dependent manner, and luteolin enhanced anti-proliferation effect of cisplatin on cisplatin-resistant ovarian cancer CAOV3/DDP cells. Flow cytometry revealed that luteolin enhanced cell apoptosis in combination with cisplatin. Western blotting and qRT-PCR assay revealed that luteolin increased cisplatin-induced downregulation of Bcl-2 expression. In addition, wound-healing assay and Matrigel invasion assay showed that luteolin and cisplatin synergistically inhibited migration and invasion of CAOV3/DDP cells. Moreover, in vivo, luteolin enhanced cisplatin-induced reduction of tumor growth as well as induction of apoptosis. We suggest that luteolin in combination with cisplatin could potentially be used as a new regimen for the treatment of ovarian cancer.